CVE-2026-54741: fallo de gravedad media en LemmyNet lemmy
Lemmy: Blocked users can edit private messages sent before the block
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
13Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 5.3epss 0.5%
Lemmy is a link aggregator and forum for the fediverse. Prior to 0.19.19 and 1.0.0-alpha.18, Lemmy blocks new private messages from a sender after the recipient blocks that sender, but the edit path skips the same block check. create_private_message checks the recipient's block list with PersonActions::read_block before inserting a message, while edit_private_message in crates/api/api_crud/src/private_message/update.rs only checks that the caller is orig_private_message.creator_id. The update then writes new content and returns the modified PrivateMessageView without consulting the recipient's block list, allowing a blocked sender to keep changing an old message that the recipient can still see and providing a post-block harassment path. This issue is fixed in versions 0.19.19 and 1.0.0-alpha.18.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Productos afectados
LemmyNet · lemmyCVEs relacionadas — LemmyNet lemmy
En el mismo producto, de las más peligrosas a las menos.
CVE-2026-54739MEDIUMLemmy: Login Endpoint User Enumeration via HTTP Response Code DifferentialEPSS 0.6%CVE-2026-54738MEDIUMLemmy: Rate limit bypass via X-Forwarded-For header spoofing in actix-web ConnectionInfoEPSS 0.6%CVE-2026-54742MEDIUMLemmy: `CollectionAdd::Featured` does not check the post is in the communityEPSS 0.5%CVE-2026-54743MEDIUMLemmy: Stored XSS via markdown image alt-text in lemmy-ui html5-embedEPSS 0.5%CVE-2024-23649HIGHAny authenticated user may obtain private message details from other users on the same instanceEPSS 0.5%CVE-2026-54740MEDIUMLemmy: Lower-ranked federated moderator can remove higher-ranked moderatorsEPSS 0.4%
Referencias
https://github.com/LemmyNet/lemmy/commit/051b317c9d14b91972bb372c67f319d6900beb93https://github.com/LemmyNet/lemmy/commit/2d169d630b86b9351e4b1dca451214b741f46150https://github.com/LemmyNet/lemmy/pull/6472https://github.com/LemmyNet/lemmy/pull/6476https://github.com/LemmyNet/lemmy/releases/tag/0.19.19https://github.com/LemmyNet/lemmy/releases/tag/1.0.0-alpha.18https://github.com/LemmyNet/lemmy/security/advisories/GHSA-46g9-847m-qf8r